Description from the author:
This API allows framebuffer device plugins to draw directly on to the
GUI's tile buffer and hence eliminates the need to memcpy(3C) tiles to
an intermediate buffer. Functions like update_hardware_cursor function
are rendered unnecessary as framebuffer device plugins can now draw the
full range of host colours. svga_cirrus will fallback to calling
graphics_tile_update without a hardware cursor if the GUI doesn't support
the new API. This patch includes implementations of graphics_tile_info,
graphics_tile_get, and graphics_tile_update_in_place (the new API) for SDL
and X11.
- new graphics update API implemented in wx and rfb
- common update functions for guis without support for the new API added (should
be removed after implementing the new API in all display libraries)